<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        .box{

            width: 500px;
            height: 10000px;
            background-color: yellow;
            background-image: url(touxiang.png);
            background-repeat: no-repeat;
            background-position:center top;
            margin:0 auto;
        }
        body{
            background-image: url(zhihu.png);
            background-size: cover;
            background-attachment: fixed;
        }
    </style>
</head>

<body>
    <div class="box"> </div>
</body>

</html>